1. Field of the Invention
This invention relates to a device and a method for using the device to plant seeds in a diamond-shaped pattern in order to obtain higher yields, accelerated canopy coverage, water savings, and herbicide savings.
2. Description of the Related Art
Planter devices have been in use for years and are for planting seeds in single or double rows. Typically a planter device includes a storage bin for storage of seed and uses a singulation system connected to the storage bin. A length of tube generally transports the singulated seed to a furrow.
Plant population, plant spacing, and yield are thought to be interrelated and these relationships need to be quantified to help growers predict yield. Spacing plants in a uniform, staggered manner promotes thicker, faster-spreading canopies that help keep the soil bed cool, moist, and better protected from erosion. Improved weed control is another benefit.
For peanuts, for example, producers in the southern United States commonly plant runner-type peanuts at a rate of approximately 20 seed/m on about 0.91 m row widths (Wehtje et al., Peanut Science, Volume 21, 16–19, 1994). The relatively high seeding rate is used as a hedge against poor emergence with the hope of attaining approximately four plants/30 cm on 0.91 m rows (Baldwin, University of Georgia Extension Service, Bulletin 1146, 1997). Higher seeding rates offer the additional benefits of (a) accelerated canopy coverage (Mozingo and Wright, Peanut Science, Volume 21, 5–9, 1994), (b) enhanced weed suppression (Hauser and Buchanan, Peanut Science, Volume 8, 74–81, 1981; Buchanan et al., In: H. E. Pattee and C. T. Young eds., Peanut Science and Technology, American Peanut Research Education Society, Inc., Yoakum, Tex., 206–249 1982), and (c) reduced tomato spot wilt virus severity (TSWV) (Brown et al., Peanut Update, University of Georgia Cooperative Extension Service Publication CSS-97-06, 1997).
Poor plant emergence, associated with inferior seed quality, pests, or adverse environmental conditions reduces plant populations and often leads to reduced yield and economic returns. Farmers trying to recapture an expected loss in income by replanting sometimes lose even more income because replanting costs may exceed the financial benefits of greater yield.
The impact of population as determined by various row and plant spacings on peanut yield has been reported with mixed results. A three year experiment in Oklahoma compared pod yields of the Spanish-type peanut Argentine on 0.25, 0.5, 0.75 and 1-m rows using 12.5, 6.7, and 3.1-cm seed spacing (Chin Choy et al., 1982). Highest yields for both irrigated and rain-fed treatments were associated with the narrowest (0.25 m) row spacing. In a study of five cultivars, it was reported that the closest (5.1 cm) seed spacing produced greater yields than 15.2 cm on 91-cm rows (Mozingo and Steele, 1989). A 2-year study (Igbokwe and Nkongolo, 1996) in Mississippi reported the effect of 10.2, 15.2, and 20.3-cm seed spacing on yield for cv. Alcon Pat using 1.07 rows. Greatest yield was associated with the 15.2-cm treatment as opposed to the narrowest rows. In another study, three of six cultivars had a significant yield increase when spacing was decreased from 30.5 to 10.2 cm/seed on 91-cm rows (Knauft et al., 1981). However, no significant yield difference was reported when spacing decreased from 15.2 to 10.2 cm.
Other studies observed diminishing yield when the population passed a critical saturation spacing. Yield of the cv. Florunner planted at 19.6, 11.9, 8.4, 6.6, and 5.3 cm/seed on 0.9-m rows progressively increased as seed spacing decreased from 19.6 to 6.6 cm/seed (Wehtje et al., 1994). However, a further reduction in seed spacing from 6.6 to 5.3 cm/seed reversed the positive trend in yield. Yield decreased when the plant population became too high. Apparently, excessive interplant competition for water, nutrients, and light reduced yield.
The relationship of plant spacing and population on grade is unclear. Knauft et al. (1981) reported five of six cultivars showed no significant difference in grade with changing population. In contrast, mozingo and Wright (1994, supra) reported significantly greater numbers of sound mature kernels (SMK), total kernels (TK), and lower other kernels (OK) for six Virginia-type cultivars associated with more compact planting patterns. Chin Choy (1982, supra) reported the highest quality was associated with 6.7 cm rather than 3.1-cm or 12.5-cm plant spacing.
Evidence highlighting the impact of plant competition expressed as the dependency of yield per plant on population has been reported for other crops. Bakelana and Regnier (1991) studied domestic oat (Avena sativa L.) and reported crop dry matter, leaf area, and tiller number per plant increased when population decreased. Zadeh and Mirlohi (1998) reported rice (Oryza sativa L.) yield per unit area was less but grain yield per plant was more when population was reduced.
Examples of planter devices include U.S. Pat. No. 4,628,841 to Powillet; U.S. Pat. No. 4,650,093 to Meyer-Bosse; U.S. Pat. No. 4,515,291 to Holmes; U.S. Pat. No. 4,928,607 to Luigi; U.S. Pat. No. 5,058,766 to Deckler; U.S. Pat. No. 5,632,212 to Barry; U.S. Pat. No. 5,351,634 to Patton; U.S. Pat. No. 4,449,642 to Dooley; U.S. Pat. No. 4,029,028 to Griffiths, U.S. Pat. No. 4,008,826 to Caree, and U.S. Pat. No. 6,173,664.
U.S. Pat. No. 4,164,190 to Newman discloses the use of a planting method to improve productivity of cereal grains and grasses. The patent discloses planting seeds in a diamond-shaped pattern with longitudinal and transverse rows of seed planting sites in which the transverse rows cross the longitudinal rows. The device uses a seed-to-seed spacing of 1 to 3½ inches along both the longitudinal and transverse rows. The disclosed device is a roller which includes a plurality of shaped projections which create an array of shallow holes in the ground arranged in the diamond-shaped pattern. After rolling, a seed drop device drops seeds into each of the holes.
While various devices are known in the art for planting seeds in order to improve yield, there still remains a need in the art for a device for planting seeds to obtain increases in production. The present invention, as described below, is different from related art devices and methods.